Cooler due for a check before summer? Book an evaporative cooler service in Perth, or if something has already failed, our evaporative air conditioner repairs team can fix it. Call (08) 9207 2370.
The good news first: most evaporative air conditioner faults are repairable, and most are preventable with an annual evaporative cooler service. When an evaporative unit stops cooling, starts leaking, or refuses to switch on, the cause is usually a single failed part rather than a dead system. The most common problems Perth technicians see are warm air instead of cool, a unit that will not turn on, water leaks, musty smells, weak airflow, noisy operation, a failed water pump, motor or belt wear, thermostat or controller faults, water valve and float problems, and worn cooling pads. Nearly all of these have a clear diagnosis and a straightforward fix.
This guide explains each of those faults, how a technician fixes them, which checks you can safely do yourself, and when repairing an ageing unit makes sense versus replacing it. If your cooler is playing up right now, you can book an evaporative air conditioner repair and skip straight to the fix.
How evaporative cooling works (and why it fails)
The basics make the faults easier to follow. An evaporative cooler sits on your roof and draws hot, dry outside air through wet cooling pads. As the water in the pads evaporates, the air temperature drops, and a large fan pushes that cooled air down through your ducts into the rooms. A small pump keeps the pads wet, a float valve controls the water level, and a controller inside the home tells the unit when to run.
Because the system relies on water, moving air, and a handful of mechanical parts working together, a fault in any one of them shows up quickly. Perth’s hot, dry summers mean these units work hard for months, and hard water leaves mineral scale on pads and components. That is why a specific symptom usually points to a specific part, and why regular servicing matters. The sections below follow the order technicians tend to work through.
Blowing warm air instead of cool
This is the number one complaint, and it almost always comes back to the water side of the system. Evaporative cooling depends on the pads being wet, so if air is moving but not cooling, the pads are probably dry and water is not reaching them.
A technician checks the water pump first, since a failed or clogged pump is the most frequent cause. They also inspect the water supply valve, the float, the distribution tubes that spread water across the pads, and the pads themselves for heavy scale that stops them absorbing water. The fix depends on the culprit: clearing or replacing the pump, freeing the water valve, flushing the distribution lines, or replacing scaled pads.
You can run a couple of safe checks first. Make sure the controller is set to “cool”, not “fan” or “vent” only, since fan-only mode deliberately blows air without wetting the pads. Then give the unit a few minutes on a cool cycle, as the pads need time to soak. If it is still warm, the fault is on the roof and needs a professional. We cover this in more depth in our guide on what to do when an evaporative cooler is blowing warm air.
The unit will not turn on
When nothing happens at all, the problem is usually electrical or controller-related rather than mechanical. A technician works from the power supply inwards: checking power at the isolator switch, testing the controller, inspecting the wiring between the controller and the roof unit, and checking the control board and any inline fuses. Common findings include a tripped circuit, a failed controller, corroded wiring on the roof, or a faulty board.
Your safe check is limited to the obvious: confirm the isolator or wall switch is on, check whether a breaker in your switchboard has tripped and reset it once if so, and make sure the controller display is lit. If the breaker trips again straight away, stop and call a professional, because a repeat trip points to a genuine electrical fault. Anything beyond flicking a switch, including opening the unit or touching wiring, is electrical work for a licensed technician.
Leaking water
Water where it should not be, whether dripping from the unit, staining a ceiling, or overflowing from the base, is worth acting on quickly to avoid ceiling or roof damage. The water level is controlled by a float valve, much like a toilet cistern. If that float sticks or fails, the base keeps filling and eventually overflows.
A technician inspects the float valve and water level, checks the base for cracks and corrosion, examines the overflow and drain lines, and looks at the inlet seals. Repairs range from adjusting or replacing the float valve to sealing or replacing a corroded base, clearing a blocked drain, or renewing a worn fitting. Older units often develop rust in the base, a common source of persistent leaks. If you see active leaking, switch the unit off at the controller, turn off its water supply if you can reach it safely, and call for help rather than climbing onto the roof. Our dedicated guide covers the causes and fixes for an evaporative cooler leaking water in more detail.
Musty or bad smells
A stale or damp smell through the vents is usually down to the water and the pads. Because the pads stay wet, they can harbour mould, mildew, and bacteria if the water sits stagnant, if the pads are old, or if the unit has been left off with water still in the base. The technician’s fix is a thorough service: draining and cleaning the base, cleaning or replacing the pads, flushing the water system, and confirming the unit’s drain or automatic bleed function is working so the water refreshes rather than stagnates. You can run the unit on fan-only mode for a while to help dry the pads, but cleaning the pads and base means roof access and is a job for a professional.
Weak or reduced airflow
If the air is noticeably weaker than it used to be, the issue is in the path the air takes: the intake, the fan, or the ducts. A technician checks the fan or blower for wear, inspects the drive belt for slippage or looseness, looks at the pads for heavy scale that restricts airflow, and checks the ductwork for blockages, crushed sections, or disconnected joints. The most common culprits are clogged pads, a loose or worn fan belt, or a fan motor not reaching full speed. Fixes include replacing the pads, tensioning or replacing the belt, and servicing the motor. There is little a homeowner can safely check here beyond confirming internal vents are open, since everything else is on the roof or in the ceiling.
Noisy operation
Evaporative units are not silent, but a new or worsening noise usually signals a mechanical part needing attention, and the type of noise is a clue. Squealing often points to a worn or loose belt or dry bearings. A rattle or vibration can be loose panels or mounting bolts. Grinding suggests worn fan or motor bearings, and knocking may be an unbalanced fan blade. A technician identifies the source, then tensions or replaces the belt, lubricates or replaces bearings, tightens panels and mounts, or balances the fan. Catching a noisy belt or bearing early is worth it, because a belt that snaps or a bearing that seizes turns a small repair into a larger one. Diagnosing it means running the unit on the roof, so it is not a DIY job, but noting what the noise sounds like and when it happens helps the technician.
Water pump failure
The pump is the small workhorse of an evaporative cooler, and because it runs constantly in water it is one of the more common parts to wear out. When it fails, water stops reaching the pads and you get warm air, so pump failure and the warm-air symptom often go hand in hand. A technician tests whether the pump is running and drawing water, checks it for sediment and scale blockages, inspects its wiring, and confirms it is priming and delivering water to the distribution lines. Sometimes the pump is simply clogged and can be cleaned; other times it is replaced. A pump replacement is a routine evaporative repair and one of the more affordable fixes, but it is firmly professional territory, since the pump is a wired, water-immersed component inside the roof unit.
Motor and belt issues
The fan motor spins the large fan that moves your cool air, and on many units it drives the fan through a belt. Both are wear items. A belt stretches, cracks, glazes, or slips over time, and a motor can wear in its bearings, run hot, or fail. Symptoms overlap with the airflow and noise faults above: weak airflow, squealing, or a unit that hums but moves little air. A technician inspects the belt for wear and tension, checks the motor’s bearings and operation, and confirms the fan spins freely at the right speed. A worn belt is a quick, inexpensive replacement and a good example of why regular servicing pays off, since a fresh belt fitted during a service avoids a mid-summer breakdown. A failed motor is a larger repair, and its cost feeds into the repair-versus-replace decision below.
Thermostat and controller faults
The controller on your wall is the brain of the system, telling the roof unit when to run, whether to cool or ventilate, and how fast to run the fan. When it fails or loses its connection to the unit, you can get a range of symptoms: no response, running when it should not, ignoring settings, or a blank or frozen display. A technician tests the controller, checks the low-voltage wiring linking it to the roof unit, and inspects the connections at both ends. Repairs are usually either replacing a failed controller or repairing the wiring, and an old or basic controller can be upgraded to one with timers and automatic water refresh. Your safe check is to confirm the display is powered and the settings are correct; the wiring and any part replacement are professional work.
Water valve and float problems
The water inlet valve and float control how much water sits in the unit’s base, ready for the pump. They sit behind two very different symptoms. If the valve or float sticks open, the base overfills and you get the leaking discussed earlier. If it sticks closed or clogs with sediment, no water enters, the pads dry out, and you get warm air. A technician inspects the float for free movement, checks the inlet valve for blockages and correct shut-off, verifies the water level, and cleans or replaces whichever part is at fault. Mineral scale and grit from the supply are the usual reasons these parts stick, another argument for periodic servicing in Perth’s hard-water conditions. Because the valve and float are inside the roof unit and connected to the plumbing, this is a job for a licensed technician.
Worn cooling pads needing replacement
Cooling pads are consumable. Over years of soaking, drying, and mineral exposure they clog with scale, break down, or lose the structure that lets air pass through while holding water. Worn pads sit behind several faults at once: reduced cooling, weak airflow, and musty smells can all trace back to pads at the end of their life. During a service or repair, a technician assesses the pad condition and replaces them when they are scaled or degraded. Fresh pads restore both the cooling performance and the airflow, and they remove a common source of odour. Pad replacement is one of the most routine parts of evaporative maintenance and is generally a modest repair, but like everything on the unit it involves roof access and is professional work.
When to repair versus replace an evaporative unit
Most evaporative faults are worth repairing, especially on a unit in otherwise good condition and only a handful of years old. A pump, belt, controller, float valve, or set of pads are all standard replacements that restore the unit at a fraction of the cost of a new system.
Replacement starts to make sense when several factors stack up: the unit is old and near the end of its life, a major part like the fan motor fails on a unit that already has other worn components, the base has corroded through and leaks persistently, repairs are becoming frequent and the cumulative cost is climbing, or the old unit is inefficient compared with a current model. A good technician will be honest about this. If a repair will get you several more reliable seasons, that is usually the sensible path; if you are repeatedly patching a unit failing in multiple places, replacement may cost less over time. Provista’s technicians can assess your unit and advise which way makes sense rather than defaulting to the more expensive option.
Common evaporative brands we repair
Perth homes run a mix of evaporative brands, and a technician who repairs them day to day knows the common ones and their quirks. The brands you will see most across Perth include:
- Breezair, a widely installed premium brand known for strong cooling performance.
- CoolBreeze, common in many Perth homes and known for reliability.
- Bonaire, a long-established evaporative and heating brand.
- Celair, another brand seen regularly across WA installations.
The core components (pump, fan, motor, belt, pads, float valve, and controller) work on the same principles across all of these, so the diagnosis and repair process follows the same logic regardless of the badge. What differs is the specific parts and controllers, which is why a technician who works across the major brands can source the right components and fix your particular model correctly.
What an evaporative repair callout involves
Knowing what to expect takes the mystery out of booking. The technician arrives and talks through the symptoms with you, since what you have noticed and when it started narrows the diagnosis quickly. They then access the roof unit safely, open it up, and inspect the key components: the pump, water level and float valve, distribution system, pads, fan, belt, motor, and wiring, along with the controller inside.
Once they have found the fault, they explain what is wrong, what the repair involves, and what it will cost before doing the work, so there are no surprises. Many common repairs, such as a pump, belt, float valve, controller, or pad replacement, can be done on the spot if the part is a standard one carried on the vehicle; a less common part is sourced and fitted on a return visit. Before leaving, a good technician runs the unit through a full cool cycle to confirm the fault is fixed. If your unit has not been serviced in a while, the callout is also a natural point to have it serviced so smaller issues are caught early.
Which checks are safe for a homeowner, and which need a professional
Evaporative units sit on the roof and combine electricity, plumbing, and moving parts, so it is worth being clear about the line. A few checks are genuinely safe to do yourself from inside the house:
- Confirm the controller is switched on, set to “cool”, and showing a lit display.
- Check whether a circuit breaker in your switchboard has tripped, and reset it once if it has.
- Make sure internal vents are open and not blocked by furniture.
- Give the unit a few minutes on a cool cycle so the pads can wet before you judge the air temperature.
- Run fan-only mode briefly to help dry the pads if there is a mild musty smell.
Everything else should be left to a licensed professional: anything involving roof access, opening the unit, the water pump, motor, belt, wiring, the float valve and plumbing, pad replacement, or any repair where a breaker keeps tripping. The reasons are simple. Working at height carries real fall risk, the unit combines electrical and water components where a mistake can be dangerous, and incorrect work can damage the unit. If you have run the safe checks above and the fault remains, that is the point to call in Provista’s evaporative repair team in Perth.
Frequently asked questions
Why is my evaporative air conditioner blowing warm air?
Are evaporative cooling repairs usually worth it, or should I replace the unit?
Can I repair my evaporative cooler myself?
Do you repair all evaporative brands in Perth?
Book your evaporative repair with Provista
If your evaporative air conditioner is blowing warm air, leaking, making a new noise, or simply will not start, the fault is very likely repairable and worth sorting before the next hot stretch. Provista’s technicians repair evaporative systems across Perth and surrounding suburbs, working through the full unit to find the real cause and fix it properly, then testing the cooling before they leave. When you are ready, book an evaporative air conditioner repair and get your home comfortable again.